Winemaking Waste Could Become Biofuel Starter

Grape pomace, the mashed up skins and stems left over from making wine and grape juice, could serve as a good starting point for ethanol production, according to a new study.

Due to growing interest in biofuels, researchers have started looking for cheap and environmentally sustainable ways to produce such fuels, especially ethanol. Biological engineer Jean VanderGheynst at the University of California, Davis, turned to grape pomace, because winemakers in California alone produce over 100,000 tons of the fruit scraps each year, with much of it going to waste.

To determine how much ethanol they could produce from pomace, VanderGheynst and her team processed pomace from the Sutter Home Winery in St. Helena, Calif., under various fermentation conditions. The researchers found that pomace from white grapes yielded the most ethanol. Winemakers only squeeze the juice out of these grapes and don’t ferment the pomace, so much of the fruits’ sugar remains. Meanwhile, red grape pomace has been fermented over long periods, so less sugar remains for ethanol production. But the scientists found that adding dilute acid to the red grape pomace boosted ethanol yields.

On average, the researchers found, grape pomace produces less than half as much ethanol as corn does by dry weight. To squeeze the maximum ethanol out of the grape waste, researchers would need to develop techniques to convert the grape’s cellulose into ethanol, says lead author Yi Zheng, a chemist at the biotechnology company Novozymes, in Denmark. But, he thinks pomace could still be a feasible feedstock because the material is readily available. Ethanol producers could make grape pomace more economically viable if they combined ethanol production with manufacture of other pomace-based products, such as fertilizers or animal feed, he says.

Information On Carboxymethyl Cellulose

Carboxymethyl cellulose(cellulose gum, cellulose,carboxymethyl ether or CMC) is a versatile, cost-effective and easy-to-use thickening agent that has numerous industrial applications. It is a substance commonly found in many household products, from certain foods to hair gels and laxatives. Cellulose gum is a key ingredient that helps maintain certain characteristics such as stabilizing a dough product, providing thickness to a gel or helping to keep two liquids mixed together. Most importantly, CMC has been shown to be safe in all of its applications.

Properties
Carboxymethyl cellulose(CAS number:9000-11-7) is registered by the Chemical Abstracts Service (CAS) of the American Chemical Society. Its CAS number is 9004-32-4. Its chemical formula is C6H7O2(OH)2OCH2COONa. It dissolves easily in both cold and hot water. It appears as a fibrous, grainy, white powder that has good thermal stability enzyme resistance, emulsification and stickiness.

Manufacture
CMC is farmed from trees and cotton and is therefore readily renewable, abundant and cheap. According to R. Sinha in the book “Outlines of Polymer Technology: Manufacture of Polymers,” the chemcial was first produced in 1917 and commercially manufactured in the 1930s. In “Twinkie, Deconstructed,” author Steve Ettlinger notes that CMC will absorb 15 to 20 times its starting weight when combined with water.

Food Uses
Been mentioned in Danisco.com, carboxymethyl cellulose is used mostly in the food and beverage industry in applications such as frozen dough, juices, concentrated beverages, dressings, soups, ice cream, processed cheeses, fruit preparation and emulsified meat products.

According to Alan Imeson in the book “Food Stabilisers, Thickeners and Gelling Agents,” cellulose gum is helpful in stabilizing the pH of protein beverages. It is also used to maintain the sweetness of high-sugar food substances such as fondants, frostings and syrups. It controls the growth of ice crystals in frozen desserts and ice cream.

Other Uses
Cellulose gum is used in oilfield drilling liquids and personal care products (toothpaste, hair gel, shampoo, lotions and ointments) and in some medicines such as laxatives and antacids. The textile industry uses cellulose gum in the production of ceramics and paper. Crude product is used on a smaller scale in laundry detergents.

Safety
Because cellulose,carboxymethyl ether passes through the human’s digestive system intact and provides no negative side effects, it can be considered completely safe. One of the testaments to the safety aspect of cellulose gum is its increasingly popular use as an ingredient in foods and beverages. It is able to provide necessary characteristics to many foods and beverages without harming the body.